Characterization and potential valorization of industrial food processing wastes

Unlocking the potential of parboiled rice mill effluent: From microalgae cultivation to bioelectricity production for sustainable development

Rice is a staple food in many Asian countries, and parboiling is a crucial process to reduce grain breakage and improve head rice yield during milling. However, this process generates substantial amounts of nutrient-rich effluent, which, if inadequately treated, leads to environmental issues such as eutrophication. The present review critically examines the parboiling process, highlighting that wastewater contains high concentrations of nitrogen, phosphorus, and organic matter with Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD). These nutrients, when utilized effectively, can support sustainable practices such as microalgae cultivation for food and biomass, biofertilizer production, and bioenergy generation, including biofuel and bioelectricity through microbial fuel cells (MFCs). Around 94 % reduction in COD levels and 90 % removal in nitrogen and phosphorus is achieved on effective utilization of nutrients in wastewater for biomass cultivation. Strategies for odor management in parboiling units are also discussed, leveraging techniques such as activated carbon adsorption and advanced oxidation processes adapted from municipal wastewater treatments. The manuscript emphasizes a circular economy approach, proposing integrated solutions for effluent reuse to minimize environmental impact and support sustainable agricultural and energy practices. Future research directions focus on scaling these technologies and optimizing their cost-effectiveness.

Exploring the antitumorigenic properties of agro-food byproducts: A comprehensive scientific review

Natural byproducts have garnered significant attention for their potential antitumorigenic properties. The current scenario sketched by the goals of circular economy approaches the research towards the utilization of agro-waste biomasses as valuable source of biological active metabolites. This comprehensive scientific review explores the various mechanisms through which these natural compounds exert anticancer effects, including apoptosis induction, cell cycle arrest, inhibition of angiogenesis, and suppression of metastasis. The review highlights key bioactive molecules such as polyphenols, flavonoids, alkaloids, and terpenoids, examining their molecular interactions with cancer cells. Furthermore, the potential of these natural byproducts as adjuvant therapies in combination with conventional treatments is discussed. By summarizing recent advancements and identifying future research directions, this review underscores the promise of natural byproducts from as a source of novel anticancer agents. A specific section is dedicated to outline the role of innovative materials, such as nanoparticles, hydrogels, and biopolymers, that are being developed to enhance the delivery and efficacy of active components. These carriers offer improved stability, targeted delivery, and controlled release of natural compounds, maximizing their therapeutic potential while minimizing side effects.

Peach Peel Extrusion for the Development of Sustainable Gluten-Free Plant-Based Flours

The food industry generates substantial waste, contributing to environmental challenges, such as pollution and greenhouse gas emissions. Utilizing by-products, particularly fruit peels that are rich in fiber, antioxidants, and vitamins, presents a sustainable approach to reducing waste, while enhancing the nutritional value of food products. Specifically, peach peel can be used to produce gluten-free flours, with increased fiber content and antioxidant properties. Extrusion technology is a highly effective method for developing these functional flours, as it improves digestibility, reduces anti-nutrients, and enhances nutrient bioavailability. This study investigates the potential of combining corn flour with peach peel flour, derived from Royal Summer peachs (RSF), at different concentrations (0%, 5%, and 15%). A factorial experimental design was utilized to evaluate the impact of RSF incorporation on the proximate composition, antioxidant capacity, and functional properties of the flour. The results indicate that flours containing 15% RSF demonstrated significant improvements in terms of the dietary fiber content (5.90 g per 100 g-1) and antioxidant capacity (ABTS•+ 745.33 µmol TE per 100 g-1), meeting the "source of fiber" labelling requirements. The glycemic index of the 15% RSF flour was reduced to 78.09 compared to non-enriched flours. The functional properties of the flour, such as swelling and gelation capacities, were also enhanced with RSF incorporation. These findings highlight the potential of RSF-enriched flours in regard to the development of sustainable, health-promoting, plant-based, and gluten-free flours.

Developing a separation system to enable real-time recovery of acetone-butanol during fermentation

Methods such as gas stripping and vacuum-assisted gas stripping (VAGS) result in significant removal of water from the bioreactor, thus requiring continuous water replenishment in the bioreactor. In this study, we developed a hydrophobic stainless steel meshes capable of selectively recovering concentrated ABE stream from the bioreactor during VAGS. Three stainless steel meshes with pore sizes of 180 µm, 300 µm, and 425 µm were made hydrophobic and oleophilic with zinc oxide (ZnO) and polydimethylsiloxane (PDMS). Butanol concentrations in the model solutions range from 3 to 10 g/L which mimic concentrations typically produced during batch ABE fermentation. The meshes were integrated in a 5-L bioreactor containing 2.5 L of operational ABE model solution followed by the evaluation of selective extraction of ABE from both cell-free and Clostridium beijerinckii-rich ABE model solutions. The results show that the 180-µm ZnO/PDMS-coated mesh retained 54-64% more water in the bioreactor without C. beijerinckii cells and 61-65% more water with cells compared to the uncoated mesh. Furthermore, the butanol concentration of condensates recovered with 180-µm ZnO-PDMS-coated mesh was up to 10.8-fold greater than that of uncoated counterpart. Our data demonstrate that the developed ZnO-PDMS mesh can recover high concentrations of ABE while selectively retaining water in the bioreactor. Additionally, this technology demonstrates the potential for real-time ABE recovery during the fermentation of lignocellulosic and colloidal materials, without the concern of clogging the separation system. KEY POINTS: • Hydrophobic mesh enhanced water retention in the bioreactor by up to 1.65-fold. • Butanol concentration in the collected condensate was increased by up to 10.8-fold. • Hydrophobic mesh is compatible with fermentation of lignocellulose.

Bioprocesses for lactic acid production from organic wastes toward industrialization-a critical review

Lactic acid (LA) is a crucial chemical which has been widely used for industrial application. Microbial fermentation is the dominant pathway for LA production and has been regarded as the promising technology. In recent years, many studies on LA production from various organic wastes have been published, which provided alternative ways to reduce the LA production cost, and further recycle organic wastes. However, few researchers focused on industrial application of this technology due to the knowledge gap and some uncertainties. In this review, the recent advances, basic knowledge and limitations of LA fermentation from organic wastes are discussed, the challenges and suitable envisaged solutions for enhancing LA yield and productivity are provided to realize industrial application of this technology, and also some perspectives are given to further valorize the LA fermentation processes from organic wastes. This review can be a useful guidance for industrial LA production from organic wastes on a sustainable view.